Those darn blend pots...

[Baldwin]

I finished following Lyle's excellent Jazz shielding pictorial a couple of nights ago, which thankfully went fairly smoothly.

However, there's a very noticeable volume drop when the blend is centered (which I've heard is often the case) but according to this diagram there's a way round it:



Trouble is, I'm not easily able to follow the diagram as I have a J/J configuration, not a P/J, so I'm not sure if putting a cap in the blend will have the required effect. Should it just go between the hot wires of both pickups?

By the way, it's a 500k blend, but one stack was around 480k and the other was around 420k. If my memory is correct (probably isn't!), the reading when detented was around 70k if that makes a difference at all.

Anyone know what to do? Have I been sent a crappy blend pot?

[i_got_a_mohawk]

It shouldnt matter that yours is a J as opposed to the PJ in the diagram.

In my basses with blend pots and volume/volume setups, when the blend is centre or both volumes are full i get a drop too. Pretty normal i believe

[Baldwin]

Yeah, I did have a very slight volume drop with the stock V/V/T
setup - it was so negligable that it wasn't a problem, but with the blend it drops to such an extent that it really isn't usable.

With your basses that have a blend, is the drop comparable to having both volumes on full or is there a massive difference?

[Baldwin]

...nobody has any ideas?

[i_got_a_mohawk]

With mine its a similar difference i'd say.

Id just try the mod you posted, see if it works

[Baldwin]

Seeing as it's currently wired up like this...



...I can't really follow the other diagram as that involves putting the cap between an unused lug on the blend and the bridge negative wiring lug. With Lyle's wiring all the negatives are connected to a ground screw in the wall of the control cavity.

I did try putting a cap between both the positive lugs (2 & 5), but I got no output at the detent. So I tried putting it between both earth lugs (1 & 6). This time at the detent I got - Capital Gold!! No idea why, but then again this flat has always had a problem with radio interference.

I could just try and exchange the blend pot, but that would sort of be admitting defeat.

[Verne Andru]

I bought a couple of blend-pots from Allparts - a 250K for my Tele and a 500K for my bass. I wired up the Tele first and lost from 20 to 30% of the volume in the center position. I pulled it out and checked it on a meter and the readings were all over the map. I sent an email to Allparts and they express shipped me 2 "metered and tested" replacements. When I checked them on my meter they read correctly and when installed there was no volume drop in the center position.

So, yes, you have crappy pots and I'd ask for some tested replacements if I were you.